The present invention is directed to a pneumatic conveyor which is capable of transporting fibrous insulating material. It is more specifically directed to a guide chute arrangement for dispensing insulating material from a storage hopper to a rotary pocket feeder for a pneumatic conveying system.
The economic benefits of a well-insulated home or building have long been appreciated in regions of the country with very cold winters or very hot summers and are beginning to be appreciated in areas with milder temperatures.
Fiberglass, rock wool, and cellulose are popular insulating materials. These fibrous materials can be placed in the walls, floors and ceilings of a building in the form of thick mats or they can be pneumatically blown or sprayed into the desired location. Many areas of a new or existing building do not lend themselves to the installation of mats, and pneumatic systems must be used to deliver the insulation.
Pneumatic systems have been widely and successfully employed to convey particulate material such as grain or flour. Typically, the particulate material is fed from a hopper into a rotary pocket feeder. The pocket feeder serves as an air lock and delivers the material to a conduit under pressure for conveyance to the desired location. Such pneumatic systems work well with particulate material but have produced less than satisfactory results when handling insulating material such as fiberglass, rock wool and cellulose. These insulating materials present special problems to pneumatic systems because they have long, light fibers and a relatively fluffy consistency that must be maintained.
The use of such fibrous materials and other light, fluffy insulating materials, such as treated paper, in existing pneumatic systems has resulted in back pressures in the chute, irregular feeding, line pulses, and the destruction of the fluffy nature of the material. This destruction greatly diminishes the insulating properties of the material. The agitators in the hopper are a particular problem in this regard. In past systems, the agitators were designed to direct particulate material downwardly and to prevent bridging above the pocket feeder. When handling fibrous insulating materials, these agitators have a tendency to grind up the materials and destroy their fluffy consistency.
Because of the above stated problems with the prior art, it is an object of this invention to provide a feeding apparatus for a pneumatic system which is particularly adapted to handle fibrous materials without destroying the fluffy consistency of those materials.
It is also an object of this invention to provide a feeding apparatus for a pneumatic system that adjustably controls the feeding rate of material into the system.
Another object is to provide a feeding apparatus for a pneumatic system that prevents back pressures from disrupting the feeding rate of the apparatus.
It is also an object to provide a feeding apparatus for a pneumatic system that uniformly feeds material into the system to prevent pulses and surges at the delivery end of the system.
A further object is to provide an apparatus with an improved manner of controlling the flow rate of material into, through and out of a guide chute. The apparatus is particularly adapted to handle fibrous materials.